The Myxococci are Gram-negative nonphotosynthetic procaryotic organisms which are motile on solid surfaces by gliding and which under nutritionally limiting conditions undergo a complex life cycle consisting of aggregation, fruiting body formation and myxospore formation.
The possible role of antibiotics in predation of the Myxobacteria has led to several contradictory reports. It was reported that Myxococcus virescens excrete antibiotics into the medium during the end of the exponential growth phase. However, the antibiotic was not purified because of its apparent instability. Other authors were unable to repeat these observations, but were able to demonstrate the M. virescens produces an antiotic against Aerobacter aerogenes, Kletter and Henis, Can. J. of Microbiol. 9,577, were unable to detect any antibiotic activity against Gram-positive or Gram-negative bacteria in cell-free filtrates of M. fulvus and M. virescens.
The only clear and direct demonstration of antibiotic production of a Myxobacterium was the discovery by Peterson et al, Can. J. Microbiol. 12; 221, that a certain species of Sorangium produces a wide -spectrum antibiotic, 1-hydroxy-6-methoxyphenazine-5,10 dioxide (Myxin.) Recent reports (1,4,5) indicate that Myxin causes a rapid degradation of DNA in E. coli.